Unit 4-Topics in Nuclear Chemistry
nuclide symbol
X a/z
isotope
same element with different number of neutrons
atomic mass units
amu
mass defect
‘m’ in E=mc^2
binding energy
‘E’ in E=mc^2
speed of light
‘C’ (3*10^8) –> (9*10^16)
joule (J)
SI unit of energy (calorie is a metric unit) –> one calorie=4.184 joules
nuclear fusion
fusion=combining
mass number
A=#n+#p
atomic number
Z=#p
mass on periodic table means 2 things!
1. mass of one mole of an element (in grams -g)
2. mass of one atom (in atomic mass unit -amu)
2. mass of one atom (in atomic mass unit -amu)
1amu
1.6605402*10^-27 (kg) && 1/12 mass of a C12 atom
mass defect=
(mass of seperated particles)-(mass whole atom)
mass lost is….
converted into energy! according to E=mc^2
joule is named after…
Joules!
the mass defect is always in…
kg
Binding energy
-the energy released when a nucleus is formed from seperate nucleons
-represents protons and neutrons forming a more stable whole nucleus
-HUGE amount of energy
-binding energy is released per mole
-represents protons and neutrons forming a more stable whole nucleus
-HUGE amount of energy
-binding energy is released per mole
mass of one atom…
slightly less than the sum of its parts
free p&n come together to form a stable nuclei..
some of their mass is converted into energy
radioactivity
spontaneous breakdown of unstable nuclei to form more stable nuclei, small particles and/or energy
nuclear stabiblity
N/Z ratio
small particles stability..
ratio= 1n:1p
large paricles stability..
ratio=1.5n:1p
transmutations of the elements
elements change into other elements
nuclear reaction equasion
a+b–>c+d
particles and/ or energies
represented w/ nucide symbols (mass/charge:proton)
proton
1 mass
+1 chargre
+1 chargre
neutron
1 mass
0 charge
0 charge
electron
1 mass
-1 charge
-1 charge
beta particle
0 mass
-1 charge (high energy e- enjected from nucleus)
-1 charge (high energy e- enjected from nucleus)
positron
0 mass
+1 charge (anti-electron: anti-matter)!!!
+1 charge (anti-electron: anti-matter)!!!
gemma ray
0 mass
0 charge (pure energy-light)
0 charge (pure energy-light)
alpha particle
4 mass
2 charge (He atom w/ no electrons)
2 charge (He atom w/ no electrons)
beta decay
neutron–>proton (in the nucleus) & spits out high energy beta particles
electron capture
nucleus absorbes one of the obating electrons (p–>n because p+e- = n)
positron emission
2 STEP PROCESS! 1. solve 2. add pointless equasion below (anit-matter +electron=2 gamma rays)
alpha decay
happens for very large atoms “quick way to looooose weight!”
radioisotope/radionuclide
any isotope that has an “unhappy” N/Z ratio& changes to fix it đ
half-life
amount of time it takes for exactly 1/2 of the origonal mass of a radioisotope to decay
radioactive decay shos which law of nature?
conservation of mass!
when using half-lifes..
either divide by 2, or muliply by 2 (total time/time of one half life)